Monday, March 12, 2018
Introduction For the past few years I have been interested in the Game Boy: I’ve written an emulator in C (without sound), I developed a physical cartridge “emulator” using a microcontroller, and most recently I’ve built a project to interface my PC with the Game Link. I’ve also played a bit with Game Boy programming.
In the past I considered buying a Game Boy flashcart so that I could run demos and other scene ROMs on real hardware comfortably, but the price of such carts is a bit high.
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Sunday, February 25, 2018
In this third and final part of the project about the Game Boy serial communication I will explain how I managed to print on the Game Boy Printer from my PC using an STM32F4 as the bridge between the two. The encoding of the image into Game Boy tiles will happen on the PC, which will send it to the STM32F4 following the packet format of the Game Boy Printer.
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Friday, February 23, 2018
In this second part of the project about interfacing the Game Boy serial communication with an embedded development board I will explain how I built a Virtual Game Boy Printer. The embedded board will be simulating a real Game Boy Printer, replying to the Game Boy following the protocol used by the Game Boy Printer so that the Game Boy sends the entire data meant to be print. This data will then be forwarded to my computer which will construct a PNG image out of it.
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Wednesday, February 14, 2018
In these series of blog posts I will write about the Game Boy serial communication protocol and how to interact with it by using an embedded development board. The code for the development board will be written in C, and the code running on the computer will be written in Rust.
The first part will consist on understanding the Game Boy serial communication protocol, becoming familiar with embedded development using the libopencm3 free/libre library and finally building a serial communication sniffer to capture the transmission of data on the Game Link Cable.
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Thursday, November 23, 2017
Introduction I’ve recently acquired a handheld ARM computer with screen and keyboard called the PocketCHIP. The main board on the device is called the CHIP, which is a tiny ARM computer capable of running Linux that is sold for $9.
After flashing it with the CHIP 4.4 GUI OS, a flavor of Debian released by Next Thing Co (the company that made the PocketCHIP) I noticed I wasn’t able to mount LUKS-encrypted partitions due to missing kernel modules.
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Monday, June 26, 2017
This post describes the upgrade procedure I follow to upgrade my Raspberry Pi Alpine Linux installation. Alpine Linux on the Raspberry Pi runs from ramfs and thus the upgrading is not straightforward. Most of the details are taken from the Alpine Linux Wiki. I’m not sure if Alpine Linux does any verification on the new downloaded release, so I’m doing that manually on another computer.
Upgrading First of all, replace the repository confiration to point to the new version:
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Tuesday, November 1, 2016
Introduction A few days ago I wanted to start doing incremental backups from my laptop to my Raspberry Pi 2 running Alpine Linux. I’ve had used rdiff-backup for some years now and I’m really happy with it. rdiff-backup is similar to rsync, in the sense that lets you synchronize folders over the network, but it has two added nice features: when synchronizing, only the differences between the files that have changed are sent; and after every synchronization, the differences between the old version of the files and the new ones is kept.
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Friday, October 21, 2016
Introduction In this post I will explain what’s required to set up a git server. We’ll use cgit to provide a web interface and also allow cloning/pulling through HTTP. ssh will also be available for cloning/pulling and pushing.
We’ll setup two groups of repositories: a public and a private one.
Cgit First of all, we’ll create a git user and move it’s home to the encrypted partition. For convenience we’ll also link that home directory to /git.
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Friday, October 21, 2016
Introduction In this post I will explain how to set up Alpine Linux for the RPi, with the necessary configuration for the RPi to power a USB hard drive, how to install lighttpd and configure automatic renewal of TLS certificates with lestencrypt.
Alpine Linux Alpine Linux can be installed on te RPi following the wiki guide.
After instalation, we add a new user which we will use for logging in:
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Thursday, October 20, 2016
Introduction I’m currently setting up a Raspberry Pi 2 as a home server for various services. I’m gonna write a series of blog posts about how I configured my Raspberry Pi to achieve my goals, which will be mainly setting up a git server and a backup server.
Choice of distribution I discovered Alpine Linux while searching lightweight distributions for the Raspberry Pi. This is a lovely small Linux distribution: one of the first things I noticed is how fast it runs on the RPi due to using a ram filesystem by default; this is specially noticeable in the RPi because usualy the operating system resides in the micro-SD card, which usually offers really slow read and write operations.
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